Magnetic Long-Range Order and Colossal Magnetoresistance Effect in Double Exchange Ladders

作     者：MA Dong-Mei ZOU Liang-Jian 马冬梅;邹良剑

作者机构：Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031 National Laboratory of Solid State MicrostructuresNanjing UniversityNanjing 210093 

出 版 物：《Chinese Physics Letters》 (中国物理快报（英文版）)

年 卷 期：2001年第18卷第9期

页      面：1264-1267页

核心收录：

学科分类：07[理学] 0701[理学-数学] 070101[理学-基础数学] 

基　　金：Supported by the Pandeng Projectthe National Natural Science Foundation of China under Grant No.19677202 the Chinese Academy of Sciences 

主　　题：orders interaction ladder 

摘      要：By applying Bogoliubov s ineguality to double-exchange(DE) ladders, we show that the ferromagnetic(FM) order is absent in the new DE systems at finite temperatures. The incorporation of Jahn-Teller electron-phonon coupling, orbital degeneracy and on-site Coulomb interaction with the DE interaction do not preserve these orders. The long-wavelength thermal fluctuations of the spins oversome the DEFM correlation and destroy the FM orders. The implication of the absence of FM order on the transport of the DE ladders is discussed.